body
{
	width: 960px;
	margin: 15px auto;
}
p
{
	margin: 0 0 20px 0;
}
p, li
{
	line-height: 20px;
}
header #page_header
{
	width: 100%;
}

header#page_header nav ul, #page_footer nav ul
{
	list-style: none;
	margin: 0;
	padding: 0;
}
#page_header nav ul li, footer#page_footer nav ul li
{
	padding: 0;
	margin: 0 20px 0 0;
	display: inline;
}

section#posts
{
	float: left;
	width: 74%;
}

section#sidebar
{
	float: left;
	width: 25%;
}

footer#page_footer
{
	clear: both;	//清除浮动，以保证footer始终位于底部
	width: 100%;
	display: block;
	text-align: center;
}
h1,h2,h3
{
	background-color: #000;
	color: white;
}
table
{
	width: 600px;
	border-collapse: collapse;
}
th,td
{
	border: none;
}

th
{
	background-color: #000;
	color: white;
}

tr:nth-of-type(even)
{
	background-color: #f3f3f3;
}
tr:nth-of-type(odd)
{
	background-color: #ddd;
}

td:last-child
{
	font-weight: bold;
}
td:nth-child(n+2)
{
	text-align: right;
}
tr:nth-last-child(-n+3)
{
	text-align: right;
	font-weight: bold;
}